CHARLESTON, S.C. — Moderate Democrats are on a mission to stop the next Bernie Sanders, starting with New York Rep. Alexandria Ocasio-Cortez.Third Way, an influential center-left group, is bringing together hundreds of elected officials, party leaders and operatives here this weekend to build a case for nominating a middle-of-the-road Democrat — not a liberal — for president in 2028.Why it matters: Centrist Democrats' efforts to shape the next election have taken on a new urgency as liberals suc...